Fekiks, I have built a couple of prototype motors myself and I applaud you knowing the time, effort and tenousisness it takes to acheive an engine at running status.

However I simply think this motor will not be recieved due to many combustion problems such as high combustion chamber surface area, poor combustion dwell time, intake charge dilution and masking which will simply make fuel efficiency and especially exhaust gas emissions impossible for todays standards.

Maybe taking this engine down the diesal road or natural gas (in its favour, the motor has very high rpm potential) might be a better option if you continue to pursue it.

"Why haven't I figured this out before this guy did?.. it's so simple" ... Beckman?
Congratulations Andrew, I guess its an ocean of new things in Your idea, and I'm sure it's not Your worry now to develop it. Lot of testing needed... but it seems to be worth the effort.
Keep the faith.

Very interesting idea! I have enjoyed the reading.
I presume a turbo-diesel version would be very efficient as I'm a bit concerned about the breathing efficience without a blower. Nevertheless, plenty of potential for testing! Andrzej, I hope you filed the patent :-)

Unfortunately, new ideas are not likely to go through with the internal combustion engine. As such, it's a very old concept and has been carefully honed through 100 years of compromises between efficiency and cost-effectiveness. To get this (or any) concept competitive with the current traditional poppet valve designs, it would require a huge amount of research (money). And then it would probably be only competitive, not superior.

In different engines and/or applications the idea might be worth checking out though.

Originally posted by observer "Why haven't I figured this out before this guy did?.. it's so simple" ... Beckman? Congratulations Andrew, I guess its an ocean of new things in Your idea, and I'm sure it's not Your worry now to develop it. Lot of testing needed... but it seems to be worth the effort.Keep the faith.

The top crankshaft revcieves lubrication just as the main piston do. Just turn a normal engine upside down ( for. eg aircraft engines ).

You could have drawn even 101 variations, and I probably did so too, but it's not about drawing and wasting pencils, it's about drawing the RIGHT thing and deciding wich way to go.
Didn't mean to tear apart Your thoughts. It would be better rather to focus them.
Debate is needed here I guess.

101 ? Mate I assure you I have thought and drawn thousands of engines searching for "Gods gift to the motoring world" as many others before me and after me will continue to do.

As a kid I would run to my Dad and show him my latest radical design to be always met with "its been done" everytime :

I love looking at different and especially radical designs (of which you can find many in this forum), but the bottom line is that they must perform a basic function being that they must produce 'X' amount of energy from 'X' amount of fuel at 'X' amount of weight and at 'X' amount of production cost.

I think it is a really good idea. Just a couple of questions/concerns:

1) In a conventional camshaft, the cam profile can be varied to control the valve movement during various phases of it's travel. This design will always give a "symmetrical" movement, since it is driven by a crank. The inlet/exhaust windows can be profiled to achieve a similar effect, but that might compromise the flow characteristics.

2) When the mixture ignites, it will exert (almost) equal pressure on all the pistons. So the engine will try to "drive" the valve-crankshaft in 2 ways, viz., (a) the timing chain/system and (b) through the piston valves. This may make the over-head piston valve system weak due to fatigue and impact loading. Resonant frequencies will have to be carefully studied to prevent a run-away system or a "stop-stop-go" system.

Probably these issues have already been thought about and resolved! Please feel free to correct me if I am wrong...

Sorry to be a sceptic, but I can see a few problems looming, won't go into everything but two biggies would be:

Uncontrollable uHC emissions, a piston passing a port will doubtless lead to both high wear and lube-oil emissions.

There are too many large crevice regions hindering effective exhaust scavenging, resulting in poor combustion, high HC and CO emissions and a poor full-load performance. Also difficult to see a way to avoid back-flow to intake system.

Always like to see new ideas though, and as someone mentioned earlier there maybe a niche market out there where emissions isn't such a big deal.

Originally posted by johnyboy Sorry to be a sceptic, but I can see a few problems looming, won't go into everything but two biggies would be:

Uncontrollable uHC emissions, a piston passing a port will doubtless lead to both high wear and lube-oil emissions.

There are too many large crevice regions hindering effective exhaust scavenging, resulting in poor combustion, high HC and CO emissions and a poor full-load performance. Also difficult to see a way to avoid back-flow to intake system.

Always like to see new ideas though, and as someone mentioned earlier there maybe a niche market out there where emissions isn't such a big deal.

J

Are you mocking me Johnyboy ?? (read post 2)

Seriously though even China ect will be frowned upon shortly about there contribution to the dark clouds above so theres not going to be a lot of places left.

After getting into it a little deeper, it seems to be pretty difficult technologically... but it also has many really NEW things in it.
And about those emissions... the combustion chamber would be really horrible if it would be not dynamic - but it IS dynamic here, so it actually might end up with better and cleaner burning.
I doubt all that oil-emissions-concerns. I think that the flow is forced psyhically in the right way, considering exhaust resonances too etc. I'll try to be a little optimistic and not to be narrod minded and i'll say that there might be more advantages than disadvantages in this idea. I guess this is the first prototype, so there's a lot of work ahead and lot of fixing the problems and testing the right model.
Open minded thinking, new, interesting.

Originally posted by crono33 am i wrong when i believe that some power is transmitted to the upper valve/pistons?

gm

Its a bit more complex than that.

Simple version, if the valve pistons are going away from their TDC's at firing point then indeed they are helping the torque of the main crank but at the cost of losing TDC compression dwell time which is not good

On the other hand if the valve pistons are still approaching their TDC's they will be increasing TDC compression dwell time which is desirable to build combustion pressure to maximum before applying leverage to the crankshaft but this pressure then forces the valve pistons/cam-crank against the main crank

This case is even a bit more complicated because the 2 valve pistons dont reach their TDC's at the same time (I havent looked at it intently enough to work it out)

Engines are give and take, come up with a bright solution and theres always a downside and thats why we still run around in constantly refined poppet valved engines.

As mentioned, emissons could become a problem when the top pistons use their oil. But the proportions of the valves seem accordingly to the upper-crankshaft size. But when the real valves are sliding in the side why not try to do the same in the main cylinder, a 3 dimensional expansion chamber. What are the advantages over the mechanical loss? What with higher revs and/or detonation? How is heat best extracted for motion?

This new 4 stroke seems exactly the opposite of a rotating valve system. No more wine-glass-bottom poppets but discs with a pie out it instead. When the 3 quarters have passed the valve opening gas can be exchanged. The thing almost looks like a beefy crankshaft-balancer so imagine the potential speed. No more rockers! Why need ram if the rpm can be doubled? It'll also be more efficient then electric valves.

But perhaps the real 4 stroke evolution has the characteristics of a 2 stroke. Direct injection existed in the 50' but only now serious applications are tried for double work of a piston engine. No moving parts in the combustion chamber (container), except the transmission-connection (rod) and the energy catcher (piston). Not the number of interdependent parts but also the functional proportions are important I think, and the environment of course...

I think this look more interesting and atleast they have started to sell there stuff allready. Maybe you should ask for partnership with them felix? As a boxer it will not colect a huge amount of oil on yout valve-pistons. They seam open minded so if not even they like your stuff you should let the project rest. Why not runn 1 crank for echaust and 1 for inlet air? Then I think you could make the construction lower and also have variable timing.

I think this look more interesting and atleast they have started to sell there stuff allready. Maybe you should ask for partnership with them felix? As a boxer it will not colect a huge amount of oil on yout valve-pistons. They seam open minded so if not even they like your stuff you should let the project rest. Why not runn 1 crank for echaust and 1 for inlet air? Then I think you could make the construction lower and also have variable timing.

Revetec is another example of a crap engine idea turned expensive development project. More victims of the torque uber alles mentality, and again fleecing large numbers of uniformed investors because of it.

They have a boxer engine with all the weight and bulk penalties associated with doubling up on cams, blocks, heads, manifolds etc. (There is a reason why boxers are not the standard engine format). To this they add a cam drive system for the pistons, with huge bearing issues. In essence all they are doing is replacing the crankshaft with a much trickier dual counterrotating three lobed camshaft.

So now they are crowing about getting three times the torque. Like that is some kind of miracle when you have three times as many piston strokes per crankshaft revolution! And they have only managed to get 150Nm out of a 1.4l engine (equivalent to about 35Nm per litre from a conventional engine or one third that of a good racecar engine (110Nm/litre) at a maximum speed of 2600 rpm (because of course the pistons are going at 7800 rpm at that speed).

But of course they haven't told the world that that is the limit in terms of their rpm. Or that a good inline four will produce three times the power they have achieved, or that high torque/low rpm is bad in that it means a much heavier and more expensive clutch and gearbox. Or that the piston driving bearings are spinning at huge speeds and are likely to pound themselves and the cam to pieces in short order.

There should be a website created to debunk idiot ideas like these. Or maybe I should loosen my morals and become the one parting the stupid people from their money.

End of rant

As a public service I will add the following keywords to hopefully open the eyes of anyone doing a search before investing.

Christiaan, Your motto help:
"Our parents assigned pain when they sent our contrary to our will for school .
We learn for personal good. I think, that it is obliged to be by whole life so, not only as there is young .But little slowly.
It can change hurts in too joy,when we little learning.This land are name: "Global". There is next natural step of motosport. "

They have a boxer engine with all the weight and bulk penalties associated with doubling up on cams, blocks, heads, manifolds etc. (There is a reason why boxers are not the standard engine format). To this they add a cam drive system for the pistons, with huge bearing issues. In essence all they are doing is replacing the crankshaft with a much trickier dual counterrotating three lobed camshaft.

As a public service I will add the following keywords to hopefully open the eyes of anyone doing a search before investing.

Revetec Crap Shit Rubbish Steaming Pile Flawed Bad Too Heavy

I wish I saw this earlier... I was under the impression that specific weight (engine weight/displacement) got better the more cylinder banks you had due to the crank (heaviest single part of the engine) getting shorter. For instance, a V6 will invariably be lighter than an equivalent straight-6, same goes for a V8... Granted there's less of an advantage with 4 cylinders, but its still there. A Subaru EJ25 motor weighs only around 140kg, and that's with iron cylinder liners and a cast iron manifold. Honda's K20 (S2000) weighs 145kg and has ceramic liners, thin-wall headers, and 500cc less displacement...

Originally posted by Stian1979 Thousands off ships world wide use this engine and is not a bold claim, but a fact.

Fuel oil consumtion down as far as 160g/kwh is curently in use.

How do you adjust valve timing on anny other engine?

What you have not mentioned is how the air gets into the cylinder and I'm kind off suprised you do not mention that problem first.

This engines nead a blower and therfore they are more exspensive to produce.

The worlds largest engines are build on this concept.

Do I have more bold claims I nead to back up?

Well, where do i start?

160g/kwh, wow, those ships must go through their fair share of oil then...

In any other engine you would find a camshaft to actuate a valve to adjust valve timing, and hence only a new camshaft would be needed to adjust those characteristics. But in your case, that engine would require a new cylinder sleeve and a complete rebuild of the upper crankcase, if not modification to the crankshaft, conrod or piston.

So far as air getting into the engine, if you would like me to critisize the engine design furhter let me know, id be happy to. So how about you clear it up for me, how does the air get into the cylinder? Why does it require a blower? Is a blower required to overcome severe pumping losses? if this is not the case, im sure with acoustic tuned manifolds you could utilise the scavenging effect during overlap to create enough vacuum at the inlet valve and raise the volumetric efficiency of the engine to a reasonable level.

I wonder why the worlds largest engines are built on this concept. Large engines would be rpm limited by large inertia forces, and most likely steady state operation and hence a design such as this would be suited to their operation.

If you ask me a true engine is designed for transient operation, such as motorsport racing, and hence any engine designed for less is out of its league.

Think of the design challenges in overcoming turbo lag or combustion chamber design in a high compression ratio, high boost operation. Thats an engine worth designing. How about the complications of lubrication in high g force loadings? Should i continue?

I guess what i could have said is, that while this engine may be suited to a niche market, it is far from perfect.

Originally posted by AndrewD In any other engine you would find a camshaft to actuate a valve to adjust valve timing, and hence only a new camshaft would be needed to adjust those characteristics. But in your case, that engine would require a new cylinder sleeve and a complete rebuild of the upper crankcase, if not modification to the crankshaft, conrod or piston.

So why can I not use diferent camshaft for this engines exhaust valve?

Originally posted by AndrewD So far as air getting into the engine, if you would like me to critisize the engine design furhter let me know, id be happy to.

Please come with it.

Originally posted by AndrewD So how about you clear it up for me, how does the air get into the cylinder? Why does it require a blower? Is a blower required to overcome severe pumping losses? if this is not the case, im sure with acoustic tuned manifolds you could utilise the scavenging effect during overlap to create enough vacuum at the inlet valve and raise the volumetric efficiency of the engine to a reasonable level.

If you can not tell why it nead a blower then maybe you should not have started making coments in the first place. I'm shure 90% off the others in here can tell that by first look.

Originally posted by AndrewD I wonder why the worlds largest engines are built on this concept. Large engines would be rpm limited by large inertia forces, and most likely steady state operation and hence a design such as this would be suited to their operation. [/B]

They are build on this concept because it's the moust fuel efficiant and cost efficiant one.They has also ben used by smaler engines like GM diesel and Detroit. Some large truck has ben using them peterbuildt if I remember corectly.

Originally posted by AndrewD If you ask me a true engine is designed for transient operation, such as motorsport racing, and hence any engine designed for less is out of its league.[/B]

A true engine is the bast design and what that is we will newer know since all exsperimantal things is baned. Did you read F1 engine regs latly?

Originally posted by AndrewD Think of the design challenges in overcoming turbo lag or combustion chamber design in a high compression ratio, high boost operation. Thats an engine worth designing. How about the complications of lubrication in high g force loadings? Should i continue?

I guess what i could have said is, that while this engine may be suited to a niche market, it is far from perfect. [/B]

How are you going to have turbolag when you got a blower

I can not see the lubrication problems your talking about witch I asume other engines would have aswell.If it's lubrication off cylinder liner you worry about then I would inform you that this engines has independent lubrication off cylinders.

So please tell me what is the perfect engine?Traditional two strokes is suited for a niche market(chain saws and mopeds) four strokes for a niche market (like auto and lawn movers)

You might find some combined diesel/steam plants, using steam turbines driven off the exhaust heat, that are a little better than that, in return for an enormous increase in plant complexity and cost.

Alternatively you could put Peltiers all the way down the exhaust, again a lot of cost for not much output.

Finally you might find some fanatics claiming better efficiency than that for Stirling engines. I iamgine that if you built one as big as that diesel engine it probably would be more efficient. It would also have about 1/3 the power output (WAG).

The fact is, oil is still cheap, it is not worth wringing every last joule out of it.

You might find some combined diesel/steam plants, using steam turbines driven off the exhaust heat, that are a little better than that, in return for an enormous increase in plant complexity and cost.

Alternatively you could put Peltiers all the way down the exhaust, again a lot of cost for not much output.

Finally you might find some fanatics claiming better efficiency than that for Stirling engines. I iamgine that if you built one as big as that diesel engine it probably would be more efficient. It would also have about 1/3 the power output (WAG).

The fact is, oil is still cheap, it is not worth wringing every last joule out of it.

There are combined cycle gas turbines that have an efficiency of about 60%, one could however argue that those are external combustion engines. With two stroke ship engines the exhaust heat is usually used for something, if not running a turbine directly, or heating water to power a turbine, it is used for other heating purposes (after first having passed the turbochargers).

The stirling engine is also an external combustion engine (or in some cases not a combustion engine at all). In any way, its efficiency will depend much on the materials used in it, like with gas turbines, as this usually limit how high temperatures that can be used.